1. Technical Field
The present disclosure relates to a light emitting device having a semiconductor light emitting element and a resin layer having an inner conductive member.
2. Background Art
Light emitting devices using a semiconductor light emitting element (light emitting element) such as a light emitting diode can be easily downsized and can attain high luminous efficiency, which allows for the use in wide range of applications. The light emitting devices using a light emitting element are roughly classified into two types: a face-up type in which a light emitting element is provided with pad electrodes on a surface opposite side of the mounting substrate, and a face-down type in which the electrodes are provided on a lower surface of a light emitting element which faces the mounting substrate.
In the face-up type, the light emitting element is mounted on leads etc., and the light emitting element and the leads are respectively connected with a bonding wire or the like. Due to this configuration, when the light emitting element is mounted on the mounting substrate, in a plan view seen from a vertical direction to the surface of the mounting substrate, a portion of the bonding wire is needed to be the outer side of the light emitting element, which limits the downsizing.
On the other hand, in the face-down type (which typically employs a flip-chip configuration), the pad electrodes disposed on the light emitting element and the conductive pattern disposed on the mounting substrate can be electrically connected with the use of a connecting means such as bumps or metal pillars which are located on an inner side than the light emitting element in a plan view seen from a vertical direction to the surface of the mounting substrate. This configuration allows downsizing of the light emitting device (particularly the dimensions in a plan view seen from a vertical direction to the mounting surface of the mounting substrate), to a degree that is close to the size of the light emitting element chip.
Recently, in order to facilitate further downsizing or to obtain further increase in the luminous efficiency, the light emitting devices of face-down type have been used, in which respectively the growth substrate (light-transmissive substrate) such as a sapphire substrate has been removed, or the thickness of the growth substrate has been reduced.
The growth substrate is used to allow growing an n-type semiconductor layer and a p-type semiconductor layer which are constituent components of a light emitting element on its surface, and also has a function of improving the strength of the light emitting device by supporting the light emitting element which has a small thickness and low mechanical strength. Thus, in a light emitting device in which after forming the light emitting element, the growth substrate is removed or the thickness of the growth substrate is reduced, for example, as shown in JP 2010-141176A, a resin layer is provided at the electrode side (a side facing the mounting substrate) to support the light emitting element, and metal pillars which penetrate the resin layer are formed, and through the metal pillars, the electrodes of the light emitting element and the conductive pattern disposed on the mounting substrate are electrically connected. With such a resin layer which contains such metal pillars, the light emitting device can be secured with sufficient strength.
On the other hand, although it is not a light emitting element, for example, JP H05-299530A and JP 2008-251794A respectively describe a method of using a metal wire, connecting a conductive pattern of a mounting substrate and a terminal for external connection disposed on a surface of the resin layer.